A Fast and Simple Method for Obtaining Microcircuit Card Information

摘要

The traditional microcircuit card generally adopts the Crypto-1 private encryption algorithm, and its main components are a pseudo random number generator (PRNG), a 48-bit linear feedback shift register (LFSR) and a nonlinear function. This paper mainly starts off from the perspective of the design flaw of the Filter Function algorithm: first, the characteristics of the random sequence are generated when the card reader swipes the card, and the same sequence is generated when the microcircuit card is re-established after each power failure; then, by controlling the time and the position of the microcircuit card, a random sequence of the moment after the microcircuit card acquires the energy is obtained, thereby implementing data modification; finally, the paper verifies by experimental methods, and the results show that the information of the microcircuit card can be indeed obtained.